 |
| Titel |
Differences in mid-latitude stratospheric winds between reanalysis data and versus radiosonde observations at Prague |
| VerfasserIn |
M. Kozubek, J. Laštovička, P. Križan |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
0992-7689
|
| Digitales Dokument |
URL |
| Erschienen |
In: Annales Geophysicae ; 32, no. 4 ; Nr. 32, no. 4 (2014-04-11), S.353-366 |
| Datensatznummer |
250121046
|
| Publikation (Nr.) |
 copernicus.org/angeo-32-353-2014.pdf |
|
|
|
|
|
| Zusammenfassung |
| Reanalysis data are very useful for studying the stratosphere. They can be
used for analysis of long-term trends (temperature, wind speed, humidity,
etc.) or analysis of global atmospheric dynamics, etc. There are various
reanalysis projects that provide outputs which are not identical. In this
paper, we mutually compare three of them, ERA-40, ERA-Interim and NCEP/NCAR,
and compare them with balloon radiosonde observations from Prague, Port Hardy
and Valentia stations. This comparison is done for wind speed and direction
at pressure levels 100 and 10 hPa and for various periods between 1957 and
2009. The results show that the differences between reanalysis vary. Wind
speed data from all three analyses reasonably agree except for the 10 hPa
historical data before 1966 and particularly ERA-40 data at the end of the
data series (1998–2001). The quality of the ERA-40 10 hPa stratospheric
wind data has been proven to be substantially worse over the last four ERA-40
years of 1998–2001 (2002) compared to previous years, both in wind speed and
wind direction. The reanalysis data results are compared with radiosonde
observations from Prague, Port Hardy and Valentia stations at 10 hPa for the
months of February between 1989 and 2009. The results show that there are
sometimes surprisingly large differences, more for ERA-Interim versus Prague
measurements. Differences in wind direction greater than 45°
(outliers) between the reanalysis data and Prague observations in wind
direction occur in Februaries predominantly when winds in Prague are in
"minor" sectors, such as north, northeast and east (easterlies), whereas
"major" sectors, particularly the dominant W (westerlies) wind sector,
exhibit almost no outliers. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|